The present invention relates generally to inductor pumps for pumping highly viscous fluid from containers. In particular, the present invention relates to platens used to push the fluid from a drum or the like.
Inductor pumps typically comprise linear pneumatic actuators that force a pipe having a platen into a drum. The platen includes a central bore that leads to a passageway in the pipe. As the platen is lowered into the drum by the pneumatic actuators, the highly viscous fluid is forced into the central bore and up the passageway. The fluid is pushed into a pump that forces pressurized fluid through a hose into spray device where an operator can dispense a metered amount of fluid into some other typically smaller container. In order to ensure advantageous operation of the inductor pump and to reduce waste, it is desirable to provide adequate sealing between the platen and drum, to prevent leakage of the fluid out of the container. Platens include flexible wipers that deflect against the drum and form a seal. The flexible wipers are selected based on the type of fluid and the type of drum in which the fluid is stored. For example, more viscous fluids require stiffer wipers. Also, some fluids are stored in containers that have variable geometry that require longer wipers or multiple wipers. Furthermore, containers have various diameters that require platens of different sizes. Attempts have been made to design platens that can be used in a variety of containers. For example, U.S. Pat. No. 5,117,998 to Handzel, which is assigned to Graco Inc., discloses a universal platen that can be used in different wiper configurations when mounted to an inductor plate hub. However, such a universal platen must be completely disassembled at the hub to replace or reconfigure the wiper. As such, there is a need for a more easily configurable universal platen.